The 116-year-old bridge is a landmark in this city of 95,000 people,
home to the University of Alabama. Residents have proposed and
gotten married next to the bridge. Children play under it. During
Alabama football season, Crimson Tide fans set up camp in its
shadow.

But with some timber pilings so badly rotted that you can stick your
hand through them, and a combination of plywood, concrete and
plastic pipe employed to patch up others, the bridge shows the
limited ability of government and industry to manage the hidden
risks of a sudden shift in energy production.

And it shows why communities nationwide are in danger.

“It may not happen today or tomorrow, but one day a town or a city
is going to get wiped out,” said Larry Mann, one of the foremost
authorities on rail safety, who, as a legislative aide on Capitol
Hill in 1970, was the principal author of the Federal Railroad
Safety Act.

Almost overnight in 2010, trains began crisscrossing the country
carrying an energy bounty that includes millions of gallons of crude
oil and ethanol. Tens of thousands of tank cars and a 140,000mile
network of rail lines emerged as a practical way to move these
commodities. But few thought to step back and take a hard look at
the industry’s readiness for the job.

Government and industry are playing catch-up with long-overdue
safety improvements, like redesigning tank cars and rebuilding
tracks and bridges.

Those efforts in the past year and a half may have saved lives and
property in many communities. But they came too late for Lac-Megantic,
Quebec, a lakeside resort town just across the Canadian border from
Maine. A train derailment there on July 6, 2013, unleashed a torrent
of burning crude oil into the town’s center. Forty-seven people were
killed.

“Sometimes it takes a disaster to get elected officials and agencies
to address problems that were out there,” said Rep. Michael Michaud,
D-Maine, a member of the House subcommittee that oversees railroads,
pipelines and hazardous materials.

Other subsequent but nonfatal derailments in Aliceville, Alabama,
Casselton, North Dakota, and Lynchburg, Virginia, followed a
familiar pattern: huge fires and spills, large-scale evacuations and
local officials furious that they hadn’t been told beforehand of
such shipments.

The U.S. Department of Transportation will issue new rules this
month to govern the transportation of flammable liquids by rail.

“Safety is our top priority,” said Kevin Thompson, a spokesman for
the Federal Railroad Administration,” both in the rule-making and
through other immediate actions we have taken over the last year and
a half.”

Nevertheless, there are other gaps in the oversight of transporting
oil by rail:

■ The Federal Railroad Administration entrusts bridge inspections to
the railroads and doesn’t keep data on their condition, unlike how
its sister agency, the Federal Highway Administration, does so for
road bridges.

■ Most states don’t employ dedicated railroad-bridge inspectors.

Only California has begun developing a bridge-inspection program.

■ The U.S. Department of Transportation concluded that crude oil
from North Dakota’s Bakken shale region posed an elevated risk in
rail transport, so regulators required railroads to notify state
officials of large shipments of Bakken crude. However, the
requirement excluded other kinds of oil shipments by raid, including
those from Canada, Texas, Wyoming, Colorado and Utah.

■ While railroads and refiners are reserving the newest, sturdiest
tank cars available for Bakken trains, they, too, have ruptured in
derailments, and Bakken and other kinds of oil are likely to be
moving around the country in a mix of older and newer cars for
several more years.

U.S. railroads moved only 9,500 cars of crude oil in 2008 but more
than 400,000 in 2013, according to industry figures. In the first
seven months of 2014, trains carried 759,000 barrels a day on more
than 200,000 cars — 8 percent of the country’s oil production,
according to the federal Energy Information Administration.

The energy boom, centered on North Dakota’s Bakken region, was made
possible by hydraulic fracturing, or fracking, a horizontal drilling
method that unlocks oil and gas trapped in rock formations. It was
also made possible by the nation’s extensive rail system.

Crude by rail has become profitable for some of the world’s richest
men. Warren Buffett, the billionaire investor, bought BNSF Railway
in 2009. It’s since become the nation’s leading hauler of crude oil
in trains. Bill Gates, the Microsoft founder and philanthropist, is
the largest shareholder in Canadian National, the only rail company
that has a direct route from oil-rich western Canada to the
refinery-rich Gulf Coast.

Although the price of oil has fallen more than 50 percent since last
January and rapidly in recent weeks, crude by rail shows few signs
of slowing down. The six largest North American railroads reported
hauling a record 38,775 carloads of petroleum in the second week of
December.

“We anticipate that crude by rail is going to stay over the long
term,” said Kevin Birn, director at IHS Energy, an information and
analysis firm and a co-author of a recent analysis of the trend.

Regulatory agencies and the rail industry may not have anticipated
the sudden increase in crude oil moving by rail. However, government
and industry had long known that most of the tank cars pressed into
crude oil service had poor safety records. And after 180 years in
business, U.S. railroads knew that track defects were a leading
cause of derailments.

Railroads are taking corrective steps, including increased track
inspections and reduced train speeds. They have endorsed stronger
tank cars and funded more training for first responders.

Ed Greenberg, a spokesman for the Association of American Railroads,
the industry’s principal trade group, said railroads began a
“top-to-bottom review” of their operations after the Quebec
accident.

“Every time there is an incident, the industry learns from what
occurred and takes steps to address it through ongoing investments
into rail infrastructure, as well as cutting-edge research and
development,” he said. “The industry is committed to continuous
improvement in actively moving forward at making rail transportation
even safer.”